A Light-Valve for the Stereophonic Sound-Film System
This paper describes a light-valve incorporating large electromagnetic damping and operating directly through the ribbon resonance region. Resonance-region response, 5 db above that at low frequencies, is equalized by a suitable equalizer to provide uniform ribbon displacement per unit driving voltage over the band 30–14,000 cycles with very nearly constant phase-shift per cycle. Problems of structure and size have furnished a mechanical design with several interesting features, among which are mechanical robustness, protection against dirt and moisture, built-in ribbon and optical adjustments, and an optical system integral with the valve structure. This unit has proved a rugged, stable, light-modulator especially free from intermodulation products.
- Print ISSN
- 0097-5834
- Published
- 1941-10
- Content type
- Original Research
- DOI
- 10.5594/J09960